Page 3 of 126
READ THIS MANUAL CAREFULLY!
It contains important safety information.
WARNING
OWNER’S MANUAL
YFZ50
This ATV should not be ridden by anyone under 6 years of age.
BW4-F8199-63-E0
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Page 5 of 126

EBU17171
INTRODUCTION
EBU17203Congratulations on your purchase of the Yamaha YFZ50. This ATV represents the result of many years of
Yamaha experience in the production of fine sporting, touring, and pacesetting racing machines. With the purchase of this Yamaha, you can now appreciate the high degree of craftsmanship and reliability that
have made Yamaha a leader in these fields.
This manual will provide you with a good basic understanding of the features and operation of this ATV.
This manual includes important safety information. It provides information about special tech-
niques and skills necessary to ride the ATV. It also includes basic maintenance and inspection proce-
dures. If you have any questions regarding the operation or maintenance of your ATV, please consult a
Yamaha dealer.
AN IMPORTANT SAFETY MESSAGE:
Read this manual completely before operating your ATV. Make sure you understand all instructions.
Pay close attention to the warning and notice labels on the ATV.
This ATV should not be operated by a child under 6 years of age.
AN IMPORTANT NOTE TO PARENTS:
This ATV is not a toy. Before you let your child ride this ATV, you should understand the instructions and
warnings in this Owner’s Manual. Then be sure your child understands and will follow them. Children differ
in skills, physical abilities and judgment. Some children may not be able to operate an ATV safely. Parents
should supervise their child’s use of the ATV at all times. Parents should permit continued use only if they
determine that the child has the ability to operate the ATV safely.UBW463E0.book Page 1 Monday, January 28, 2019 10:22 AM
Page 7 of 126
EBU17331
IMPORTANT MANUAL INFORMATION
EBU17344FAILURE TO FOLLOW THE WARNINGS CONTAINED IN THIS MANUAL CAN RESULT IN SERIOUS IN-
JURY OR DEATH.
Particularly important information is distinguished in this manual by the following notations:TIPProduct and specifications are subject to change without notice.
The ATV you have purchased may differ slightl y from the figures shown in this manual.
This is the safety alert symbol. It is used to alert you to potential per-
sonal injury hazards. Obey all safety messages that follow this sym-
bol to avoid possible injury or death.
A WARNING indicates a hazardous situation which, if not avoided,
could result in death or serious injury.
A NOTICE indicates special precautions that must be taken to avoid
damage to the vehicle or other property.
A TIP provides key information to make procedures easier or clearer.
WARNING
NOTICETIP
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EBU17421
TABLE OF CONTENTS
LOCATION OF THE WARNING AND
SPECIFICATION LABELS .............................. 1-1
SAFETY INFORMATION ................................ 2-1
DESCRIPTION................................................ 3-1Left view ...................................................... 3-1
Right view.................................................... 3-1
Controls and instruments............................ 3-2
INSTRUMENT AND CONTROL
FUNCTIONS ................................................... 4-1 Main switch ................................................. 4-1
Handlebar switches .................................... 4-1
Engine stop switch with lanyard ................. 4-2
Throttle lever ............................................... 4-3
Speed limiter ............................................... 4-3
Front brake lever ......................................... 4-5
Rear brake lever .......................................... 4-6
Parking brake .............................................. 4-6
Kickstarter ................................................... 4-7
Fuel tank cap .............................................. 4-8
Fuel ............................................................. 4-9
Fuel cock................................................... 4-10 Starter (choke) ......................................... 4-12
Seat .......................................................... 4-13
Rear shock absorber ................................ 4-13
PRE-OPERATION CHECKS .......................... 5-1 Fuel ............................................................. 5-3
Engine oil .................................................... 5-3
Transmission oil .......................................... 5-3
Front and rear brakes ................................. 5-3
Throttle lever ............................................... 5-3
Drive chain .................................................. 5-3
Tires ............................................................ 5-3
Chassis fasteners ....................................... 5-6
Instruments and switches........................... 5-6
OPERATION .................................................. 6-1 Starting a cold engine................................. 6-1
Starting a warm engine............................... 6-3
Engine break-in........................................... 6-3
Parking........................................................ 6-3
Parking on a slope ...................................... 6-4
Accessories and loading ............................ 6-5UBW463E0.book Page 1 Monday, January 28, 2019 10:22 AM
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1-1
1
EBU29681
LOCATION OF THE WARNING AND SPECIFICATION LABELS
EBU36153Read and understand all of the labels on your ATV. These labels contain important information for safe and
proper operation.
Never remove any labels from your ATV. If a label becomes difficult to read or comes off, request a re-
placement label from your Yamaha dealer.UBW463E0.book Page 1 Monday, January 28, 2019 10:22 AM
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2-6
2
TEACHING YOUR CHILD TO OPERATE THE
ATV
WARNING
EWB00081Never let your child ride an ATV without close
adult supervision (a child under 6 should not
ride this ATV even with adult supervision).
Promptly correct your child if he or she begins
to ride beyond his or her abilities and, if neces-
sary, intervene by pulling the cord (lanyard) to
stop the engine.
If the child rides beyond his or her abilities, or
rides in terrain that is too difficult, he or she
may lose control of the ATV, causing an acci-
dent.
Introduce new riding areas slowly and make
sure the riding area matches your child’s skill
level. You must make the commitment to your child’s
proper use of the ATV. Your child must rely upon
you to be sure he or she has the development,
proper training, and proper equipment, as well as
an appropriately sized ATV and an appropriate rid-
ing area. Be sure your child is ready to learn how to ride
As a parent, your first step is to decide when your
child has the strength, skills, and judgment to
learn how to operate an ATV safely. Re-evaluate
your child’s readiness before every use; a child
who is too tired or distracted should not be al-
lowed to operate the ATV.
Be sure your child is properly trained
Your child should take a certified training course.
Training will continue with you as the instructor, so
you should be sure you thoroughly understand
proper riding techniques before continuing to in-
struct your child. Go through this Owner’s Manual
page by page with your child and be sure he or
she understands how to operate the ATV properly.
Be sure your child is wearing all the proper
safety equipment
Your child must always wear an approved motor-
cycle helmet that fits properly. Your child should
also wear the safety equipment described in the
Riding Your ATV section of this manual.UBW463E0.book Page 6 Monday, January 28, 2019 10:22 AM
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2-8
2
WARNING
EWB00073Avoid Carbon Monoxide Poisoning
All engine exhaust contains carbon monoxide,
a deadly gas. Breathing carbon monoxide can
cause headaches, dizziness, drowsiness, nau-
sea, confusion, and eventually death.
Carbon Monoxide is a colorless, odorless,
tasteless gas which may be present even if you
do not see or smell any engine exhaust. Deadly
levels of carbon monoxide can collect rapidly
and you can quickly be overcome and unable
to save yourself. Also, deadly levels of carbon
monoxide can linger for hours or days in en-
closed or poorly ventilated areas. If you experi-
ence any symptoms of carbon monoxide
poisoning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREATMENT.
Do not run engine indoors. Even if you try to
ventilate engine exhaust with fans or open
windows and doors, carbon monoxide can
rapidly reach dangerous levels.
Do not run engine in poorly ventilated or par-
tially enclosed areas such as barns, garages,
or carports.
Do not run engine outdoors where engine
exhaust can be drawn into a building through
openings such as windows and doors.
WARNING
EWB02592When transporting the ATV in another vehicle,
be sure it is kept upright and that the fuel cock
is in the “OFF” position. Otherwise, fuel may
leak out of the carburetor or fuel tank.
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4-4
4
Vehicle speed limiter
1. Loosen the locknut.
2. To increase the maximum engine power available and the maximum speed of the ATV,
turn the adjusting screw in direction (a). To
decrease the maximum engine power avail-
able and the maximum speed of the ATV, turn
the adjusting screw in direction (b). Do not
turn the adjusting screw out more than 14.5
mm (0.57 in) or the throttle cable could be
damaged. Always make sure the throttle lever
free play is adjusted to 2.0–3.2 mm (0.08–
0.13 in). (See page 8-22.) WARNING! Im-
proper adjustment of the speed limiter and
throttle could cause throttle cable damage
or improper throttle operation. You could
lose control, resulting in an accident.
[EWB00242]
3. Tighten the locknut.
Engine speed limiter plate
When the engine speed limiter plate is installed,
engine speed is limited to 5200 r/min. When this
plate is removed, top engine speed (7500 r/min) is
available.
Remove the plate as follows. 1. Remove panel A. (See page 8-9.)
2. Loosen the screws, and then remove the plate as shown.1. Locknut
2. Adjusting screw
3. No more than 14.5 mm (0.57 in)
1
2
(b)
(a)
3
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